Closure means for withstanding high pressures



y 1965 J. o. BENNETT 3,182,850

CLOSURE MEA OR WIT ed Ja NS. F HSTANDING HIGH PRESSURES Fil n. 28, lessFIG. 2.

6 |2 Q FIG. I.

INVENTOR.

JOHN D. BENNETT BY [3 ifivm ATTORNEYS struments into a bore well.

United States Patent Ofi ice 3,182,855 Patented May 11, 196

3,182,850 CLOSURE MEANS FOR WI'II-ISTANDING HIGH PRESSURES John D.Bennett, Richardson, Tex., assignor to Sun Oil Company, Philadelphia,Pa., a corporation of New Jersey Filed Jan. 28, 1963, Ser. No. 254,135 4Claims. (Cl. 220-46) This invention relates to closure means forwithstanding high pressures and, more particularly, to a seal foreffectively preventing diffusion of fluids, and particularly highpressure gases, over longperiods of time.

The present invention relates to a seal which is of the general typedisclosed in Patents 3,040,927 and 3,074,589, issued June 26, 1962, andJanuary 22, 1963, to Preston E. Chaney, which type of seal hasparticular utility in sealing instrument cases adapted to be loweredinto bore holes for the purpose of making various types of measurementstherein. Although the seals disclosed in the aforementioned patent andapplication are highly effective, neither completely overcomes all ofthe problems which are raised by the environmental conditions underwhich the sensitive instruments must operate. For example, someinstruments such as differential pressure gauges require that no gasdiffusion occurs across the seal which separates internal chambers fromthe pressure existing in the bore hole; the latter of which pressuresmay be of the order of 4,000 p.s.i. On the other hand, it is necessarythat the seal be easily assembled and disassembled in the field and, tothis end, it is highly desirable that all portions of the seal bere-usable so that a minimum of extra parts and sealing equipment must bemaintained on hand in the field.

rings generally provide excellent seals, but despite their effectiveactions resulting from mechanical deformation, their materials are notthemselves impervious to diffusion, particularly of gases, under extremepressure conditions. 7

It is a general object of the present invention to provide an improvedhigh pressure seal which effectively prevents gas diifusion thereacross.

It is a further object of the invention to provide a seal which iseasily assembled and disassembled and in which all portions of the sealare completely re-usable.

The attainment of the foregoing and other objects of the invention willbecome apparent from the following description when read in conjunctionwith the accompanying drawing in which:

FIGURE 1 is an axial section illustrating the arrangement of the seal toprevent external high pressure fluids from entering a protective casing;and

FIGURE 2 is an axial section illustrating the arrangement of the 'sealin order to prevent internal high pressure fluids from escaping from ahousing.

Referring first to FIGURE 1, numeral 10 generically designates aprotective casing in the form of a cylinder of which portion 12 isdesigned so as to withstand the maximum pressures which are expected tobe encountered in the intended use. For example, the casing may be usedto lower various types of logging or other measuring in- The casing maybe composed of any rigid material including both magnetic andnonmagnetic materials such as steel and Monel metal or the like so longas the portion 12 is capable of withstanding the environmental pressureswithout unacceptable deformation.

tohouse instruments to protect them against the externz pressures towhich the outside of casing 10 is subjecter Of course, the opposite endof the casing may also b provided with a similar closure member and sealor may be otherwise closed as by integral partition.

The seal 20 includes three essential elements 22, 24 an as each of whichwill now be described in detail.

Element 22 is a cylindrical integral portion of casin 10 having athickness such that it may be deflected ir wardly by the high pressuressurrounding the casing This deformability is illustrated by the dottedline pos tion of portion 22 although it is to be understood the theamount of deflection has been greatly exaggerated fc purposes of claritysince it may be of the order of onl a few thousandths of an inch.Portion 22 has a slidin fit over the reduced diameter cylindricalportion 32 c plug 14 and its free edge abuts shoulder 30' at the en ofthe reduced portion. The base end of portion 22 abut shoulder 34 whichis formed by a groove 28. Thus, th portion 22 is capable of deformingand deflecting inwardl to the dotted line position inwardly of groove 28unde external pressure.

Element 24 is a conventional O ring which may b composed of Teflon orViton or the like. 0 ring 24 i received in the end of groove 28 which isremote fro: the threaded plug end and is covered by casing portion 2extending axially thereacross.

Also disposed in groove 28 is an annular ring 26 whici is composed of adeformable metal such as soft lead 0 a soft metallic alloy such as thoseof lead, tin and/ or his muth, or a solid but soft mercury amalgam ofvariou metals. Ring 26 is initially confined within the spac bounded by0 ring 24, groove 28, shoulder 34 and POI tion 22, the latter of whichextends axially across th outer surface of the ring as well as 0 ring24. Howevel the amount of lead comprising ring 26 is initially chose:such that the lead does not completely fill the above dc fined space.Rather, a slight amount of clearance i deliberately provided between theexternal surface of rin 26 and the internal surface of portion 22 whenthe latte is in the cylindrical, non-deflected position illustrated bthe solid lines. This provision insures the easy assembl of plug 14 andcasing 10 since the lead does not exten radially outwardly of thesurface defined by shoulders 3. and 34. Thus, the plug is easilyreceived within the cat ing and may be threaded to a position of tightengage ment between the end of portion 22 and the shoulder St The lead,or equivalent, ring may be cast in place b providing a dam about thegroove 28. But in view 0 the conditions indicated hereafter it may alsobe provide by winding, with overlapping tapered ends a strip 0 shapedlead within the groove 28. Ultimate pressur will close the resultingjoint as will be evident hereafter A stretched O ring may be put inplace after the lead rin is located in the groove.

When the plug and casing have been assembled 21 shown in FiGUR'E l andexternal pressure is applied i the assembly, the seal and the variousportions thereo act in the following manner:

As the assembly is lowered into the bore hole, the pres sure surroundingthe casing gradually increases and, dur ing this period of relativelylow pressures, O ring 24 i forced axially against the lead ring and isdistorted in th usual fashion to provide an initial seal for preventingth flow of fluid thereacross. The pressure exerted on th 0 ring causesthe lead ring to distort to swell outwardl as it is axially compressed.This swelling produces tigi engagement of the lead with the internalsurface of por tion 22 so that the previous clearance is no longerpreser between these elements and a slight amount of lead ma start toextrude between the flange 34 and the portio:

But as the pressure increases, the portion 22 is :ed inwardly into tightengagement with the flange 34 venting substantial extrusion. The resultis that the 1, under compression, molds itself tightly to all of itsrounding surfaces, flowing into the most minute des'sions and soproviding an extremely tight metal-to- :al closure against flow. Thelead acts as the final seal prevents any diffusion of fluid thereacrossso long as aforementioned external pressure is maintained, the:al-to-metal contact being completely impervious to v. Diffusion cannotoccur through the lead.

Vhen the assembly is raised from the bore hole, the :rnal pressuregradually decreases so that portion 22 irns to its original position andthereby disengages the 1 ring. Thus, the assembly may be laterdisassembled to easily without interference of the lead. As the ssuredecreases, ring 24 again performs the primary ling function, as it didduring the pressure increasing iod, the pressure gradient becoming solow that the ing affords effective sealing so that at no time does usionoccur across the seal.

rom the foregoing description it will be apparent that of the elements24, 26 and 22 form cooperating parts a single seal wherein each of theelements coacts with other elements to provide the combined sealingaction. addition, it will be apparent that the provision of eleats 24and 26 in the same groove is of critical imporce since these twoelements must directly aflect one tther in order to achieve the sealingaction set forth einabove.

eferr-ing now to FIGURE 2, it will be apparent that seal and theelements thereof are identical to those viously discussed and they areaccordingly designated the same numerals primed. The sole difference been the arrangements shown in FIGURES 1 and 2 re- :s'in the location ofelement 22 within housing It? so t this element is deflected bythe'application of internal 1er than external pressure. Since thestructural elents and their function is identical to that previouslycribed with regard to FIGURE 1, further description :he FIGURE 2embodiment is unnecessary.

iince numerous modifications and alterations will beae readily apparentfrom the foregoing description, it o be understood that the invention isnot to be limited erwise than as required by the following claims. Vhatis claimed is:

. In combination, a casing member, a closure memcooperating therewith toform a chamber, a groove )ne of said members, an O ring packing and adeforme metallic ring in mutually abutting and contacting ttionship insaid groove, the other of said members 'ing a deformable portionextending across said rings is to be deflected toward said groove andthereby comss said rings upon the application of high pressure inst saiddeformable portion, said rings being confined hin said groove inabutting contact so that as said demable portion is deflected towardsaid groove to cornss said rings, said rings transmit distortingmovement from one to the other to effect a tight seal between saiddeformable portion and said groove containing member.

2. In combination, a casing member, a closure member cooperatingtherewith to form a chamber, a groove in one of said members, an O ringpacking and a deformable lead ring in mutually abutting and contactingrelationship in said groove, the other of said members having adeformable portion extending across said rings so as to be de: flectedtoward said groove and thereby compress said rings upon the applicationofhigh pressure against said deformable portion, saidringsbeing-confined within said groove in abutting contact so that assaid deformable portion is deflected toward said groove to compress saidrings, said rings transmit distorting movement from one to the other toefiect a tight seal between said deformable portion and said groovecontaining member.

3; In combination, a casing member, a closure member cooperatingtherewith to form a closed chamber within said casing member, a highpressure fluid within said chamber, a groove in one of said members, an0 ring packing and a deformable metallic ring positioned in mutuallyabutting and contacting relationship in said groove, the other of saidmembers having a deformable portion exposed to' said high pressure fluidextending across said rings so as to be deflected toward said groove andthereby compress said rings under the force exerted by said highpressure fluid, said rings being confined within said groove in abuttingcontact with each other and with the groove surface so that as saiddeformable portion is deflected toward said groove to compress saidrings, said rings transmit distorting movement from one to the other toeffect a tight seal between said deforming member and said groovecontaining member.

4. In combination, a casing member, a closure member cooperatingtherewith to form a closed chamber within said casing member, saidcasing member being subjected to external high pressure fluid, a groovein one of said members, an O ring packing and a deformable metallic ringpositioned in mutually abutting and contacting relationship in saidgroove, the other of said members having a deformable portion exposed tosaid high pressure fluid extending across said rings so as to bedeflected toward said groove and thereby compress said rings under theforce exerted by said high pressure-fluid, said rings being confinedwithin said groove in abutting contact with each other and with thegroove surface so that as said deformable portion is deflected towardsaid groove to'compress said rings, said rings transmit distortingmovement from one to the other to eflect a tight seal between saiddeforming member and said groove containing member.

References Cited by the Examiner UNITED STATES PATENTS 2,570,406 10/51Troshkin et al. 2,764,311 9/56 Blackman 220-46 3,040,927 6/62 Chaney220-46 THERON Primary Examiner.

1. IN COMBINATION, A CASING MEMBER, A CLOSURE MEMBER COOPERATING THEREWITH TO FORM A CHAMBER, A GROOVE IN ONE OF SAID MEMBERS, AN O RING PACKING AND A DEFORMABLE METALLIC RING IN MUTUALLY ABUTTING AND CONTACTING RELATIONSHIP IN SAID GROOVE, THE OTHER OF SAID MEMBERS HAVING A DEFORMABLE PORTION EXTENDING ACROSS SAID RINGS SO AS TO BE DEFLECTED TOWARD SAID GROOVE AND THEREBY COMPRESS SAID RINGS UPON THE APPLICATION OF HIGH PRESSURE AGAINST SAID DEFORMABLE PORTION, SAID RINGS BEING CONFINED WITHIN SAID GROOVE IN ABUTTING CONTACT SO THAT AS SAID DEFORMABLE PORTION IS DEFLECTED TOWARD SAID GROOVE TO COMPRESS SAID RINGS, SAID RINGS TRANSMIT DISTORTING MOVEMENT FROM ONE TO THE OTHER TO EFFECT A TIGHT SEAL BETWEEN SAID DEFORMABLE PORTION AND SAID GROOVE CONTAINING MEMBER. 